That's not really the best way to go about it. Some bows aren't supposed to be turned past 2 turns, like my synergy for example. Others can be backed out WAY more than 4 turns.
Going slow and checking with a scale as described is a bit safer. When at all possible, it's always best to consult with the manufacturer's spec chart.
That being said, I've seen bows "killed" in many different ways, but I've never seen one damaged from being backed too far out. Possible? Absolutely. But it would take some doing in most cases.
Swapping limbs, it'll surprise you just how far you gotta back that bow out, and how much those limbs relax. If they're backed out too far, you'll most likely notice that it shoots really, really poorly because the limbs are free to rattle. Keep shooting it, and that may cause problems. But it would be a trick to get one to come undone while you were adjusting it.
Also, it's my experience that bows shoot best tightened up all the way (poundage maxed out). If OP decides to go lower, a limb change is the way to go.
And finally, you are 100% correct on stating that not everybody has a good, local shop. I think every bowhunter should own a press, and know how to use it. It's not a rocket ship. Compound bows look fancy, but they're really very simple beasts.